Radiometric-microbiologic assay fo vitamin B-6: analysis of plasma samples

Journal Article · Sun Nov 01 00:00:00 EST 1981 · J. Nutr.; (United States)

OSTI ID:5589467

Guilarte, T R; McIntyre, P A

A radiometric microbiologic assay for the analysis of vitamin B-6 in plasma was developed. The method is based on the measurement of 14CO2 generated from the metabolism of DL-l-14C-valine (L-l-14C-valine) by Kloeckera brevis. The assay is specific for the biologically active forms of the vitamin, that is, pyridoxine, pyridoxal and pyridoxamine, and their respective phosphorylated forms. The biologically inert vitamin B-6 metabolite (4-pyridoxic acid) did not generate a response at concentrations tested. The radiometric technique was shown to be sensitive to the 1 nanogram level. Reproducibility and recovery studies gave good results. Fifteen plasma samples were assayed using the radiometric and turbidimetric techniques. The correlation coefficient was r . 0.98. Turbid material or precipitated debris did not interfere with the radiometric microbiologic assay, thus allowing for simplification of assay procedure.

• Research Organization: Department of Environmental Health Sciences, The Johns Hopkins University School of Hygiene and Public Health, Baltimore, MD
• OSTI ID: 5589467
• Journal Information: J. Nutr.; (United States), Vol. 111:11
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
62 RADIOLOGY AND NUCLEAR MEDICINE
CARBON 14 COMPOUNDS
ISOTOPE APPLICATIONS
PYRIDOXINE
RADIOASSAY
CARBON DIOXIDE
SENSITIVITY
VALINE
AMINO ACIDS
AZINES
CARBON COMPOUNDS
CARBON OXIDES
CARBOXYLIC ACIDS
CHALCOGENIDES
HETEROCYCLIC COMPOUNDS
HYDROXY COMPOUNDS
LABELLED COMPOUNDS
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PYRIDINES
VITAMIN B GROUP
VITAMINS
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